Alfred Dawes | Are you really on a diet?
I face them every day: Frustrated patients who are trying to lose weight that just doesn’t seem able to come off. They try every diet from cabbage soup to ketogenic. Expensive injections and shakes work for a while but the weight just keeps coming back. They exercise but there is barely a flicker on the scale. What am I doing wrong, Doc?
To understand weight gain and weight loss, there is a simple formula that you must learn:
Weight change = calories consumed – calories burned.
It is as simple as that. If you consume more calories than you are burning, those excess calories will be stored as fat. If you are burning more calories than you are taking in, only then will you lose weight. The big problem that most of us have is that we underestimate how many calories we are consuming, and overestimate how much we burn through exercise. The second major issue is that we think we are in a caloric deficit when we are not.
Let us look at both of these impediments to weight loss.
If we were to religiously track how many calories we consume for the day, most of us would be in for a surprise. One often repeated phrase is “I hardly eat”. While that may be true in terms of meal frequency and size, the source of the calories can be the cause for a caloric surplus.
Most nutritional labels only give the caloric values of the serving size. But there are multiple servings in a container. For example, per serving for a tin of corned beef, there are 130 calories. That seems low until you realise that there are six servings in the regular size tin. That is 780 calories.
The calories in a pack of crackers is not the 120 you see per serving, but 420 calories. So a half a tin of bully beef and crackers is over 800 calories. And you haven’t drank the juice that could be another 200 calories. That’s 1,000 calories from one light meal.
A round bun as a snack – 450 calories; sweet biscuit or chips, easily 400 calories. Sandwiches can be calorie dense when the condiments and type of meat is factored in. And then there is bread. Two slices, 260 calories, and we haven’t added the butter yet.
Even fruits and shakes with their high sugar content are hidden sources of calories. A salad, with croutons, dressings, cheese, etc., can be over 1,000 calories.
You may be eating healthy, but one snack or bad meal totally destroys your caloric deficit. Many persons fall into the trap where they feel they are eating healthy but they are still taking in too many calories.
HOW MUCH WE BURN
On the other side of the equation, we overestimate how much we burn at the gym. Are we looking at the time spent working out or the quality of the effort? You could be in the gym for an hour and burn only 200-300 calories. You feel hungry after the workout or buy into the idea that you must fuel your body with sports drinks or more food.
What actually happens is that you cancel out the calories burned and are back at square one.
Exercises such as walking and running burn more calories the heavier you are. But as you get slimmer, there is less weight for your muscles to move around so you require less energy, that is, you burn less calories for the same distance than when you were bigger.
To understand how many calories we need to eat and burn, we need to know what is our Basal Metabolic Rate (BMR). The BMR is the minimum number of calories required to run our bodies when at rest.
Organs such as the brain, heart, liver and kidneys need calories to fully function. Our skeletal muscle primarily burns fat at rest and is the contributor to the BMR we can increase consciously. Depending on your age, sex and weight, your BMR can range from 1,200 to 2,500 calories per day on average.
Our daily activities such as walking and any manual labour add to this BMR and we get our total caloric requirements per day. The big problem is that we do not know what is our BMR and so we overestimate how many calories we require for daily activities.
I myself was surprised that my BMR was 10 per cent lower than what was expected for my age and size. For others, it’s even worse. You may be looking at nutritional labels giving calories as a percentage of a 2,000cal/day diet when your BMR is only 1,500 cals/day!
One of the main issues why I don’t endorse crash diets and teas is that they lead to a severe caloric deficit. When your body is in such a deficit, it reaches for any available stored energy. That could be fat and protein from skeletal muscle. If you are not protecting your muscles with enough protein in your diet, your muscle mass shrinks, and with that its contribution to your BMR. Your daily caloric requirements fall and as soon as you are off the diet, the weight returns with a vengeance.
Applying these principles in a consistent manner instead of quick fixes can lead to long-term weight loss in the overweight but not the morbidly obese. That is where it gets complex. I’ll get into that in my next article.
Dr Alfred Dawes is a general, laparoscopic and weight loss surgeon; Fellow of the American College of Surgeons; former senior medical officer of the Savanna La Mar Public General Hospital; former president of the Jamaica Medical Doctors Association. @dr_aldawes. Email feedback to email@example.com and firstname.lastname@example.org